Improvement in hydraulic jack and press



Patented Dec; ,25, van?.l

Hydraulic Jack and Press.

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UNITED STATEsv5 PATENT OEEICE.

FREDERICK C.. HUNTER, OE MONCTON, NEW BRUNSWICK, CANADA, AssIeNOR OE ONE-HALE HIs RIGHT To JOHN M. REID, OE sAME PLACE.

IMPROVEMENTlN HYDRAULIC JACK AND PRESS.

Specification forming part of Letters Patent No. 198,620, dated December 25,1877 application led To all Iwhom it may concern:

Be it known that I, FREDERICK G. HUNTER,

of the town of Moncton county of Westmoreland, Province of New Brunswick, in the Dominion of Canada, have invented va new and useful Improvement in Hydraulic Jack and Press, of which the following is a specification, reference being had to the accompanying drawings, forming part of the same, of which- Figure l is an elevation of a hydraulic jack. Fig. 2 is a vertical central section of the` same on the lines w, Fig. 1. Fig..3 is a similar view of the lower end of the ram, showing the valves in a position different from that of the same partin Fig. 2; and Fig. 4 is a crosssection on line y y of Fig. l.

My vinvention relates to the devices for opening the valves inthe ram and the pumpplunger contained within it, to permit the passage of the fluid from the cylinder into the chamber in the interior of the ram; and consists of a lever pivoted in the plunger-shaft just above the upper end of the stem of the plunger-valve, which projects upward into a recess in said shaft, and aledge or stop on Vthe interior face of the ram, the parts being stem or shaft G o f the piston extending to the upper end of the ram, and is there connected to a crank-lever, H, whereby, by means of the socket I and pump-lever J, it is actuated in the usual way. a is the ingress-valve of the pumpplunger, and c its stem, which extends upward in al recess in the plunger. The pump-barrel being of less diameter than the chamber G, there is formed at its upper end a ledge, d.

e is a short lever, pivoted in a mortise or 4ledge d.

November 6, 18717.

recess cut transversely into or through the stem G of the plunger. This lever e is so arranged with reference to G and the upper end of the valvestem c that when the said valve is closed, as shown in Fig. 3, the inner end of the lever e will be thrown up, as seen in said Fig. 3.

f is the egress-valve of the pump, the stem g of which extends upward, through an aperture in the lower end of the ram, into the barrel D of the pump when the valve is closed. The two valve-stems are of somewhat less diameter than the apertures in which theywork, so that when the valves areopen iiuid may pass through said apertures. l 1

h is a cap or head screwed to the lower end of the plunger E, so arranged that when the said plunger is forced downward below a certain point it will strike against the upper end of the stem g and force the egress-valve f open. At the same time that the outer end of the lever e strikes against the ledge d, thus rel D of the pump, and l l are apertures through the head or cap h.

Theoperation of the parts described is as follows: The pump is worked for forcing uid from the reservoir C into the case A by moving the plunger only a certain 'distance downward at each stroke, stopping short always of bringing the lever e into contact with the This operation may be continued until the ram is raised to the required height. Then, when it is desired to lower the ram by the return of the fluid into the reservoir C, the plunger is thrust farther down below the point where the lever e comes in contact with said ledge,'when the inner end of said lever will be tilted' downward, forcing downV and opening the valve a. At the same time the head or cap h will strike against the stem g of the valve f, and open that also, thus opening a passage for the fluid back from the case A into the reservoir C. l

The pump-lever J has a spur, m, on one side, which, when turned downward, strikes against a lug, n, and thus prevents too low a thrusti of the pump-plunger during the operation of f pumping. Then, by reversing 'said lever 'in the socket I, it may be so depressed as to carry down the pump-plunger far enough to open the valves, as above described.

rIhe shaft K, by which the crank-lever -H is actuated, works in a recessed bearing in the head of the ram, as seen in Fig. 4. It is provided with a packing, o o, as seen in that fig` ure, to prevent the escape of the fluid from the reservoir C. v

In place of the ledge d, as described, being made to perform the ofce of a stop to the lever e, a lug or annular or other projection may be formed on the inner face of the chamber C, to perform the said office.

What I claim as new, and desire to secure' by Letters Patent, is-

The combination, in a hydraulic jack or press, of a lever pivoted to the pump-plunger or its shaft, and a stop, so arranged that by the downward movement of the plunger beyond a certain point the said lever is made to open the valve of said plunger, substantially -as described.

Witness my hand this 30th day of October, 187 7.

FREDERICK G. HUNTER.

Witnesses:

J. WORTMAN, W. B. CLARK.v 

